Ments



(NO Model.)

S. BERGMANN. COMPOSITION COATING FOR PAPER TUBES. No. 482,718. Patented Sept. 20, 1892.

WITNESSES: INVENTOH UNITED STATES PATENT OFFICE.

SIGMUND BERGMANN, OF NEW YORK, N. Y., ASSIGNOR, BY MESNE ASSIGN- MENTS, TO THE INTERIOR CONDUIT AND INSULATION COMPANY, OF

SAME PLACE.

COMPOSITION COATING FOR PAPER TUBES.

SPECIFICATION forming part of Letters Patent No. 482,718, dated September 20, 1.892.

Application filed March 4, 1891- Serial. No. 383,704. (No specimens.)

To all whom it may concern.-

Be it known that I, SIGMUND BERGMANN, of New York, in the county and State of New York, have invented a certain new and use- 5 fullmprovement in Coatings for Paper Tubes,

of which the following is a specification.

Tubes made of paper are commonly used as conduits for electric wires and are useful for many other purposes.

The object of my improvement is to render such tubes fireproof and alkali-proof.

My improvement consists in a coating for a paper tube or conduit, consisting of plumbago mixed with a solution of plaster-of-paris 15 or equivalent adhesive substance.

The accompanying drawing is a side view of a tube partly coated in accordance with my improvement.

The tube which I have represented is comzo posed of a number of strips of paper spirally wound upon a mandrel in such manner as to break joints. The jointsa of one of the strips may be seen in the drawing. This tube is coated either inside or out, or both, and 2 5 throughout any portion of its length with a mixture of plumbago and a solution of plaster-of-paris or equivalent adhesive substance. The plumbago will be ground into powder and mixed with the solution of plaster-0fparis or other adhesive substance. Afterward it may be applied by means of a brush I SIGMUN D BERGMANN.

Witnesses:

OLIET WISE, JAMES NAGLE. 

